VC选择文件夹对话框，updata(false)应该是对话框的功能，而不是控件的功能

void CHomeworkCompareDlg::OnBnClickedBtnBrowser()
{
// TODO: 在此添加控件通知处理程序代码;

char szDir[MAX_PATH];
BROWSEINFO bi;
ITEMIDLIST *pidl;
bi.hwndOwner = this->m_hWnd;


bi.pidlRoot = NULL; //如果指定NULL,就以“桌面”为根;
bi.pszDisplayName = szDir;
bi.lpszTitle = "请选择作业目录"; //;
bi.ulFlags = BIF_STATUSTEXT | BIF_USENEWUI | BIF_RETURNONLYFSDIRS;
bi.lpfn = NULL;
bi.lParam = 0;
bi.iImage = 0;
pidl = SHBrowseForFolder(&bi);
if(pidl == NULL)
{
return;
}
if (!SHGetPathFromIDList(pidl, szDir))
{
return;
}
else
{
m_str_hw_dir = szDir;
}
UpdateData(FALSE);
}